NamedCsvReader should have support for returning default value if field is not present

[anuragagarwal561994]

Is your feature request related to a problem? Please describe.
We have a use-case where we have 2 different csv files one where 3 columns are present and another where 5 columns are present. We want to be able to keep the fields as required and 2 optional. In case we do row.getField('NOT_PRESENT_COLUMN') as of now we get an error, we can instead have a method like row.getFieldOrDefault(field_name, default_value) which if the field is not present will return the default value.

However this should not be confused with the data being present as null.

Describe the solution you'd like
Described above

[osiegmar]

Thank you for bringing this up!

Just added this functionality by 5ebb7d5. This allows something like this:

try (var csv = NamedCsvReader.builder().build("col1,col2\nfoo").stream()) {
    csv.forEach(rec -> {
        var col1 = rec.findField("col1").orElse("default");
        var col2 = rec.findField("col2").orElse("default");
        System.out.printf("col1: %s, col2: %s%n", col1, col2);
    });
}

Will be part of version 3 which will be released within the next few months.

[anuragagarwal561994]

Thanks for update, actually later I realised that I can instead use csvRow.getFields() which gives a map and then I can check containsKey

I was about to close the issue.

[osiegmar]

Go ahead and use it, if it fits your need. As that methods requires another "bigger" object (Map) being built for every record, I'm happy to also offer a more elegant and less resource consuming way to access optional fields.